The present invention relates generally to replaceable fluid containers, and exemplary embodiments of the invention relate more specifically to mechanisms for preventing residual ink from accumulating in the sealed fluid interconnect port of a replaceable ink container.
Ink jet printers are well known in the art. The most common type of ink jet printer uses thermal excitation of the ink to eject droplets through tiny nozzles, or orifices, onto a print media. Other ink jet mechanisms, such as the use of piezoelectric transducers as ink droplet generators, are also well understood. With all ink jet technologies, the ink jet pen is typically mounted on a carriage which is scanned across the print media; dot matrix manipulation of the droplets provides alphanumeric character and graphics printing capabilities. To provide a color printing capability, pens for each primary color (such as cyan, magenta, and yellow) are commonly used, typically in addition to black.
The ink jet pen itself may have a self-contained reservoir for storing ink and providing appropriate amounts of ink to the printhead during a printing cycle. These self-contained pens are commonly referred to in the art as print cartridges. If reusable, semi-permanent pens rather than print cartridges are employed, ink is either supplied from a remote off-axis (or off-board) ink reservoirs, or the ink reservoirs are mounted on the carriage with the pens.
In a typical ink jet printing system with semi-permanent pens and replaceable ink supplies, the replacement ink supplies are generally provided with seals over the fluid interconnects to prevent ink leakage and evaporation, and contamination of the interconnects during distribution and storage.
One form of replaceable ink jet ink container comprises a rigid container substantially filled with a capillary foam material, with a fluid interconnect port located at the bottom of the container. Fluid connection from the ink container to the printhead is made through a tower having a fine screen at its apex, which passes through the fluid interconnect port and presses against the capillary material. At the time of manufacture and prior to filling the container with ink, the fluid interconnect port of the container may be sealed with a sealing tape, which is removed by a consumer prior to installing the ink container in a printer.
A problem encountered with the use of sealing tape on fluid interconnects in this type of container is that residual ink may be present in the sealed fluid interconnect port, which was either deposited there during the container fill process, or was forced out of the capillary material when the container was dropped during shipping and handling. Particularly with pigmented inks, residual ink in the fluid interconnect port may be resistant to re-adsorption into the capillary material. When the sealing tape is removed for installation of the ink supply into the printer, the residual ink may contact the fingers or clothing of the installer, or be flung off the tape. Care must therefore be exercised when removing the sealing tape to avoid contact with any residual ink. The residual ink may also react with the adhesive on the sealing tape, contaminating the ink in the container; or in multi-colored ink containers, one color of ink may contaminate another.
There is therefore a need for mechanisms which reduce the occurrence of residual fluid in the fluid interconnect region of a replaceable container.
Venting mechanisms are provided for allowing air to replace fluid in the sealed fluid interconnect port of a container substantially filled with a capillary material, thus enabling absorption of residual fluid into the container capillary material. In one embodiment, the venting mechanisms include small ribs formed on the floor of the container body to space the capillary material away from the floor, thus allowing air to flow along the container floor to the interconnect port.
Other aspects and advantages of the present invention will become apparent from the following detailed description, taken in conjunction with the accompanying drawings, illustrating by way of example the principles of the invention.